From Keith Alexander, National Trust
Do 91av writers not read 91av? Your article implies that
the health of a tree can be judged by whether or not it is rotten inside
(4 March, p 9).
In a previous letter
(21 November 1998, p 63), I explained why this is not
true and that decay of the dead heartwood of trees has nothing to do with tree
health. The technology of detecting decay and hollows may be marvellous, but the
understanding of tree biology is certainly not.
Cirencester, Gloucestershire
